The Low Velocity Impact Response of Foam Core Sandwich Panels with a Shape Memory Alloy Hybrid Face-Sheet.

Hao Li,Yanfei Liu,Zhenqing Wang,Min Sun,Zhengwei Yu

doi:10.3390/ma11112076

Abstract

Most foam core sandwich panels are sensitive to the impact load because of the poor toughness of thin composite face-sheets and the low strength of foam core. Superelastic shape memory alloy (SMA) wires have been applied to enhance the impact damage resistance of composite laminates in recent decades. To improve the impact damage resistance of foam core sandwich panels and to protect the foam core, SMA wires were incorporated into the face-sheets of foam core sandwich panels in this work. Eight new types of SMA hybrid sandwich panels were designed, and low-velocity impact tests were carried out at an impact energy of 35 J. The damage morphology of the impacted sandwich panels was identified by visual inspection and scanning electron microscope technology. Results indicate that the impact damage resistance of the SMA hybrid sandwich panels is enhanced. The damage area in the hybrid sandwich panels is greatly reduced and a decrease of 85.63% can be reached in the bottom face-sheet. The maximum contact force has an improvement of 28.15% when the two layers of SMA wires are incorporated into the bottom face-sheet.

Highlights

Due to the excellent mechanical properties in terms of high strength and stiffness to weight ratios, good corrosion resistance and ease of fabricating and repair, composite sandwich structures have been widely applied in many fields such as aerospace, the shipbuilding industry and wind turbine blades in recent decades [1,2,3,4]
The maximum contact force has an improvement of 28.15% when the two layers of shape memory alloy (SMA) wires are incorporated into the bottom face-sheet
New foam core sandwich panels with SMA hybrid face-sheets are designed for better impact damage resistance

Summary

Introduction

Due to the excellent mechanical properties in terms of high strength and stiffness to weight ratios, good corrosion resistance and ease of fabricating and repair, composite sandwich structures have been widely applied in many fields such as aerospace, the shipbuilding industry and wind turbine blades in recent decades [1,2,3,4]. Most sandwich panels are inherently sensitive to localized damage caused by transverse loads, which is attributed to the poor toughness of thin laminated face-sheets and low strength of core materials. Low velocity impact as one type of common localized load can damage sandwich panels. The presence of different damage modes (matrix cracking, fiber breaking, delamination, skin-core debonding, core crushing, etc.) results in a significant decrease in the mechanical performance of sandwich panels [5,6,7,8,9,10]. Comprehensive research has been done on the mechanical response of sandwich panels subjected to low velocity impact. The impact damage mechanisms of sandwich panels made of different composite skins and core materials have been investigated by many researchers [11,12,13,14,15,16]

Methods

Results

Conclusion